Dunn's numbers are huge themselves, with his 1336 drives so far this year already well past the 1263 drives he had in 2009, his busiest season in New Zealand.
The North America season is the calendar year, so the now 29-year-old has driven more horses and nearly as many winners as his best New Zealand's season at just the halfway stage of their season.
"It has been gone remarkably well," Dunn told the Herald. "I knew it would be hard to break into over here because I had tried before so for it to go this well is very satisfying.
"I have had a lot of support from some really good people and I've also worked pretty hard."
I drove right through the winter to get established and that really helped. But it is a life that doesn't leave a lot of room for anything else.
That has meant a huge change in lifestyle for Dunn, who might have driven three or four days a week on average in New Zealand but now often drives at two meetings in a day and drives in some capacity almost every day.
"There is a lot of racing over here so the lifestyle is simply that, racing," says Dunn. "I have had days where I have driven 25 horses at two different meetings, and that is just the actual races.
"And then we have the qualifiers [trials] which often has like a dozen heats for the babies alone at this time of the year.
"And if you want to get good drives you need to be driving at the qualifiers too.
"So I drove right through the winter to get established and that really helped.
"But it is a life that doesn't leave a lot of room for anything else."
Dunn has already tasted elite level success in the Fan Hanover in Canada and finished second in the North America Cup there and when the Herald caught up with him yesterday, he had just driven a treble at Yonkers.
But what comes next is more important, with the richest races just around the corner as well as the dream of getting on a special juvenile pacer.
"There are a lot of really big races coming up and that will be fun.
"But it is also very different from back home. The outsiders don't tend to win here quite as often and obviously we don't get driving fees, so driving in all those races doesn't matter as much as stakes do.
"It has gone incredibly well though so I have no plans to come back home to drive any time soon," says the 10-time New Zealand premiership winner.